Bytescodes contains various arrays which are all effectively compile time constants, but are not defined as such. Instead the data is filled in by bytecodes_init() during VM initialization. We can make everything except _flags compile time constants easily by using some macros and C++14 constexpr. We can also ensure the bytecodes data is in the right order by asserting such in debug builds removing the reasoning for not making it a compile time constant in the first place.

_flags might be able to be made compile time constant using some constexpr tricks, but that will not be tackled in this enhancement.